The disclosure relates to instruments or tools used in performing surgery on a patient. More particularly, the disclosure relates to cutting instruments using electrodes to seal or cauterize tissue.
Clinicians use surgical instruments, including debriders such as microdebriders, to shave, cut, resect, abrade, or remove tissue, bone, or other body materials from a surgical site during surgery including endoscopic surgery. An example of such an instrument includes a rotating cutting blade on an elongated tube. The elongated tube is fit within an elongated outer tube having a cutting window exposing the cutting blade. The cutting blade is rotated within and with respect to the outer tube. The outer tube and inner tube are coupled to a handpiece. The handpiece typically includes a motor coupled to inner tube to rotate the cutting blade with respect to the handpiece. In one example, an actuator on the handpiece controls the rotation of the motor. A clinician is thus able to manipulate the location and rotation of the cutting blade to remove material from the surgical site. In some examples, a vacuum is applied through the inner tube to remove material that is cut with the blade. Many instruments also supply an irrigation fluid to the surgical site. The surgical instruments provide precise mechanical cutting at a surgical site through a low or minimally invasive incision or entry point in the patient.
One issue presented with surgical cutting instruments such as debriders involves the ability to control bleeding. If bleeding is not controlled, blood can obscure the view of the surgical site, adversely affect the precision of the cutting or severing tissue, and prolong the surgery. Too much blood loss can cause trauma to the patient that may require a blood transfusion. Electrosurgical instruments are often used to control bleeding in such circumstances. Electrosurgical instruments can be used to cauterize, coagulate/desiccate or simply reduce blood flow by controlling electrosurgical energy applied to the tissue. Small blood vessels, e.g., those having a diameter of less than about two millimeters, can be coapted through coagulation, i.e., the process of desiccating tissue where the tissue cells are ruptured and dried. Larger blood vessels may be coapted through sealing, i.e., the process of liquefying the collagen in the tissue so that it reforms into a fused mass. In some instances, a second surgical device is used to control bleeding either before or after body material is cut. Some electrosurgical cutting instruments include the ability to cut body material and control bleeding with the same device.